I address the problem of indefiniteness in quantum mechanics: the problem that the theory, without changes to its formalism, seems to predict that macroscopic quantities have no definite values. The Everett interpretation is often criticised along these lines, and I shall argue that much of this criticism rests on a false dichotomy: that the macroworld must either be written directly into the formalism or be regarded as somehow illusory. By means of analogy with other areas of physics, I develop the (...) view that the macroworld is instead to be understood in terms of certain structures and patterns which emerge from quantum theory (given appropriate dynamics, in particular decoherence). I extend this view to the observer, and in doing so make contact with functionalist theories of mind. (shrink)

Presents a guide to the basics of quantum mechanics and measurement.

Appearance and Reality: An Introduction to the Philosophy of Physics addresses quantum mechanics and relativity and their philosophical implications, focusing on whether these theories of modern physics can help us know nature as it really is, or only as it appears to us. The author clearly explains the foundational concepts and principles of both quantum mechanics and relativity and then uses them to argue that we can know more than mere appearances, and that we can know to some extent the (...) way things really are. He argues that modern physics gives us reason to believe that we can know some things about the objective, real world, but he also acknowledges that we cannot know everything, which results in a position he calls realistic realism. This book is not a survey of possible philosophical interpretations of modern physics, nor does it leap from a caricature of the physics to some wildly alarming metaphysics. Instead, it is careful with the physics and true to the evidence in arriving at its own realistic conclusions. It presents the physics without mathematics, and makes extensive use of diagrams and analogies to explain important ideas. Engaging and accessible, Appearance and Reality serves as an ideal introduction for anyone interested in the intersection of philosophy and physics, including students in philosophy of physics and philosophy of science courses. (shrink)

We develop a systematic approach to quantum probability as a theory of rational betting in quantum gambles. In these games of chance, the agent is betting in advance on the outcomes of several (finitely many) incompatible measurements. One of the measurements is subsequently chosen and performed and the money placed on the other measurements is returned to the agent. We show how the rules of rational betting imply all the interesting features of quantum probability, even in such finite gambles. These (...) include the uncertainty principle and the violation of Bell's inequality among others. Quantum gambles are closely related to quantum logic and provide a new semantics for it. We conclude with a philosophical discussion on the interpretation of quantum mechanics. (shrink)

This is one of the most important books on quantum mechanics to have appeared in recent years. It offers a dramatically new interpretation that resolves puzzles and paradoxes associated with the measurement problem and the behavior of coupled systems. A crucial feature of this interpretation is that a quantum mechanical measurement can be certain to have a particular outcome even when the observed system fails to have the property corresponding to that outcome just prior to the measurement interaction.

This book is about how to understand quantum mechanics by means of a modal interpretation. Modal interpretations provide a general framework within which quantum mechanics can be considered as a theory that describes reality in terms of physical systems possessing definite properties. Quantum mechanics is standardly understood to be a theory about probabilities with which measurements have outcomes. Modal interpretations are relatively new attempts to present quantum mechanics as a theory which, like other physical theories, describes an observer-independent reality. In (...) this book, Pieter Vermaas summarises the results of this work. The book will be of great value to undergraduates, graduate students and researchers in philosophy of science, and physics departments with an interest in learning about modal interpretations of quantum mechanics. (shrink)

A proof is given, at a greater level of generality than previous 'no-go' theorems, of the impossibility of formulating a modal interpretation that exhibits 'serious' Lorentz invariance at the fundamental level. Particular attention is given to modal interpretations of the type proposed by Bub.

A number of arguments have been given to show that the modal interpretation of ordinary nonrelativistic quantum mechanics cannot be consistently extended to the relativistic setting. We find these arguments inconclusive. However, there is a prima facie reason to think that a tension exists between the modal interpretation and relativistic invariance; namely, the best candidate for a modal interpretation adapted to relativistic quantum field theory, a prescription due to Rob Clifton, comes out trivial when applied to a number of systems (...) of physical interest. However, it is far from clear whether this difficulty for the modal interpretation is traceable to relativistic invariance per se or to the infinite number of degrees of freedom involved. In any case, the proponents of the modal interpretation have work to do. (shrink)

Appearance and Reality: An Introduction to the Philosophy of Physics addresses quantum mechanics and relativity and their philosophical implications, focusing on whether these theories of modern physics can help us know nature as it really is, or only as it appears to us. The author clearly explains the foundational concepts and principles of both quantum mechanics and relativity and then uses them to argue that we can know more than mere appearances, and that we can know to some extent the (...) way things really are. He argues that modern physics gives us reason to believe that we can know some things about the objective, real world, but he also acknowledges that we cannot know everything, which results in a position he calls "realistic realism." This book is not a survey of possible philosophical interpretations of modern physics, nor does it leap from a caricature of the physics to some wildly alarming metaphysics. Instead, it is careful with the physics and true to the evidence in arriving at its own realistic conclusions. It presents the physics without mathematics, and makes extensive use of diagrams and analogies to explain important ideas. Engaging and accessible, Appearance and Reality serves as an ideal introduction for anyone interested in the intersection of philosophy and physics, including students in philosophy of physics and philosophy of science courses. (shrink)